: CHD files typically offer a significant reduction in file size (often 20% to 50% smaller than uncompressed BIN/CUE files).

: CHD can reduce file sizes by 40% to 50% .

Maintains CD-DA (Red Book audio), subchannel data (for libcrypt protection), and accurate read speeds during emulation.

It sounds like you're looking for versions of PSX (PlayStation 1) ROMs/ISOs.

For PSX specifically, CHD supports:

List the CHD filenames inside (e.g., Game (Disc 1).chd , Game (Disc 2).chd ).

CHD is a lossless compression format originally designed for MAME, but it works wonders for PS1 discs. You can often shrink your library by 20% to 50% without losing a single bit of game data.